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gro: Allow tunnel stacking in the case of FOU/GUE
[linux/fpc-iii.git] / fs / proc / array.c
blobdca04edb6b9052293ac4d7b38d112dcf2bd325a4
1 /*
2 * linux/fs/proc/array.c
3 *
4 * Copyright (C) 1992 by Linus Torvalds
5 * based on ideas by Darren Senn
6 *
7 * Fixes:
8 * Michael. K. Johnson: stat,statm extensions.
9 * <johnsonm@stolaf.edu>
10 *
11 * Pauline Middelink : Made cmdline,envline only break at '\0's, to
12 * make sure SET_PROCTITLE works. Also removed
13 * bad '!' which forced address recalculation for
14 * EVERY character on the current page.
15 * <middelin@polyware.iaf.nl>
16 *
17 * Danny ter Haar : added cpuinfo
18 * <dth@cistron.nl>
19 *
20 * Alessandro Rubini : profile extension.
21 * <rubini@ipvvis.unipv.it>
22 *
23 * Jeff Tranter : added BogoMips field to cpuinfo
24 * <Jeff_Tranter@Mitel.COM>
25 *
26 * Bruno Haible : remove 4K limit for the maps file
27 * <haible@ma2s2.mathematik.uni-karlsruhe.de>
28 *
29 * Yves Arrouye : remove removal of trailing spaces in get_array.
30 * <Yves.Arrouye@marin.fdn.fr>
31 *
32 * Jerome Forissier : added per-CPU time information to /proc/stat
33 * and /proc/<pid>/cpu extension
34 * <forissier@isia.cma.fr>
35 * - Incorporation and non-SMP safe operation
36 * of forissier patch in 2.1.78 by
37 * Hans Marcus <crowbar@concepts.nl>
38 *
39 * aeb@cwi.nl : /proc/partitions
40 *
41 *
42 * Alan Cox : security fixes.
43 * <alan@lxorguk.ukuu.org.uk>
44 *
45 * Al Viro : safe handling of mm_struct
46 *
47 * Gerhard Wichert : added BIGMEM support
48 * Siemens AG <Gerhard.Wichert@pdb.siemens.de>
49 *
50 * Al Viro & Jeff Garzik : moved most of the thing into base.c and
51 * : proc_misc.c. The rest may eventually go into
52 * : base.c too.
53 */
54
55 #include <linux/types.h>
56 #include <linux/errno.h>
57 #include <linux/time.h>
58 #include <linux/kernel.h>
59 #include <linux/kernel_stat.h>
60 #include <linux/tty.h>
61 #include <linux/string.h>
62 #include <linux/mman.h>
63 #include <linux/proc_fs.h>
64 #include <linux/ioport.h>
65 #include <linux/uaccess.h>
66 #include <linux/io.h>
67 #include <linux/mm.h>
68 #include <linux/hugetlb.h>
69 #include <linux/pagemap.h>
70 #include <linux/swap.h>
71 #include <linux/smp.h>
72 #include <linux/signal.h>
73 #include <linux/highmem.h>
74 #include <linux/file.h>
75 #include <linux/fdtable.h>
76 #include <linux/times.h>
77 #include <linux/cpuset.h>
78 #include <linux/rcupdate.h>
79 #include <linux/delayacct.h>
80 #include <linux/seq_file.h>
81 #include <linux/pid_namespace.h>
82 #include <linux/ptrace.h>
83 #include <linux/tracehook.h>
84 #include <linux/string_helpers.h>
85 #include <linux/user_namespace.h>
86
87 #include <asm/pgtable.h>
88 #include <asm/processor.h>
89 #include "internal.h"
90
91 static inline void task_name(struct seq_file *m, struct task_struct *p)
92 {
93 char *buf;
94 char tcomm[sizeof(p->comm)];
95
96 get_task_comm(tcomm, p);
97
98 seq_puts(m, "Name:\t");
99 buf = m->buf + m->count;
100
101 /* Ignore error for now */
102 buf += string_escape_str(tcomm, buf, m->size - m->count,
103 ESCAPE_SPACE | ESCAPE_SPECIAL, "\n\\");
104
105 m->count = buf - m->buf;
106 seq_putc(m, '\n');
107 }
108
109 /*
110 * The task state array is a strange "bitmap" of
111 * reasons to sleep. Thus "running" is zero, and
112 * you can test for combinations of others with
113 * simple bit tests.
114 */
115 static const char * const task_state_array[] = {
116 "R (running)", /* 0 */
117 "S (sleeping)", /* 1 */
118 "D (disk sleep)", /* 2 */
119 "T (stopped)", /* 4 */
120 "t (tracing stop)", /* 8 */
121 "X (dead)", /* 16 */
122 "Z (zombie)", /* 32 */
123 };
124
125 static inline const char *get_task_state(struct task_struct *tsk)
126 {
127 unsigned int state = (tsk->state | tsk->exit_state) & TASK_REPORT;
128
129 BUILD_BUG_ON(1 + ilog2(TASK_REPORT) != ARRAY_SIZE(task_state_array)-1);
130
131 return task_state_array[fls(state)];
132 }
133
134 static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
135 struct pid *pid, struct task_struct *p)
136 {
137 struct user_namespace *user_ns = seq_user_ns(m);
138 struct group_info *group_info;
139 int g;
140 struct task_struct *tracer;
141 const struct cred *cred;
142 pid_t ppid, tpid = 0, tgid, ngid;
143 unsigned int max_fds = 0;
144
145 rcu_read_lock();
146 ppid = pid_alive(p) ?
147 task_tgid_nr_ns(rcu_dereference(p->real_parent), ns) : 0;
148
149 tracer = ptrace_parent(p);
150 if (tracer)
151 tpid = task_pid_nr_ns(tracer, ns);
152
153 tgid = task_tgid_nr_ns(p, ns);
154 ngid = task_numa_group_id(p);
155 cred = get_task_cred(p);
156
157 task_lock(p);
158 if (p->files)
159 max_fds = files_fdtable(p->files)->max_fds;
160 task_unlock(p);
161 rcu_read_unlock();
162
163 seq_printf(m,
164 "State:\t%s\n"
165 "Tgid:\t%d\n"
166 "Ngid:\t%d\n"
167 "Pid:\t%d\n"
168 "PPid:\t%d\n"
169 "TracerPid:\t%d\n"
170 "Uid:\t%d\t%d\t%d\t%d\n"
171 "Gid:\t%d\t%d\t%d\t%d\n"
172 "FDSize:\t%d\nGroups:\t",
173 get_task_state(p),
174 tgid, ngid, pid_nr_ns(pid, ns), ppid, tpid,
175 from_kuid_munged(user_ns, cred->uid),
176 from_kuid_munged(user_ns, cred->euid),
177 from_kuid_munged(user_ns, cred->suid),
178 from_kuid_munged(user_ns, cred->fsuid),
179 from_kgid_munged(user_ns, cred->gid),
180 from_kgid_munged(user_ns, cred->egid),
181 from_kgid_munged(user_ns, cred->sgid),
182 from_kgid_munged(user_ns, cred->fsgid),
183 max_fds);
184
185 group_info = cred->group_info;
186 for (g = 0; g < group_info->ngroups; g++)
187 seq_printf(m, "%d ",
188 from_kgid_munged(user_ns, GROUP_AT(group_info, g)));
189 put_cred(cred);
190
191 #ifdef CONFIG_PID_NS
192 seq_puts(m, "\nNStgid:");
193 for (g = ns->level; g <= pid->level; g++)
194 seq_printf(m, "\t%d",
195 task_tgid_nr_ns(p, pid->numbers[g].ns));
196 seq_puts(m, "\nNSpid:");
197 for (g = ns->level; g <= pid->level; g++)
198 seq_printf(m, "\t%d",
199 task_pid_nr_ns(p, pid->numbers[g].ns));
200 seq_puts(m, "\nNSpgid:");
201 for (g = ns->level; g <= pid->level; g++)
202 seq_printf(m, "\t%d",
203 task_pgrp_nr_ns(p, pid->numbers[g].ns));
204 seq_puts(m, "\nNSsid:");
205 for (g = ns->level; g <= pid->level; g++)
206 seq_printf(m, "\t%d",
207 task_session_nr_ns(p, pid->numbers[g].ns));
208 #endif
209 seq_putc(m, '\n');
210 }
211
212 void render_sigset_t(struct seq_file *m, const char *header,
213 sigset_t *set)
214 {
215 int i;
216
217 seq_puts(m, header);
218
219 i = _NSIG;
220 do {
221 int x = 0;
222
223 i -= 4;
224 if (sigismember(set, i+1)) x |= 1;
225 if (sigismember(set, i+2)) x |= 2;
226 if (sigismember(set, i+3)) x |= 4;
227 if (sigismember(set, i+4)) x |= 8;
228 seq_printf(m, "%x", x);
229 } while (i >= 4);
230
231 seq_putc(m, '\n');
232 }
233
234 static void collect_sigign_sigcatch(struct task_struct *p, sigset_t *ign,
235 sigset_t *catch)
236 {
237 struct k_sigaction *k;
238 int i;
239
240 k = p->sighand->action;
241 for (i = 1; i <= _NSIG; ++i, ++k) {
242 if (k->sa.sa_handler == SIG_IGN)
243 sigaddset(ign, i);
244 else if (k->sa.sa_handler != SIG_DFL)
245 sigaddset(catch, i);
246 }
247 }
248
249 static inline void task_sig(struct seq_file *m, struct task_struct *p)
250 {
251 unsigned long flags;
252 sigset_t pending, shpending, blocked, ignored, caught;
253 int num_threads = 0;
254 unsigned long qsize = 0;
255 unsigned long qlim = 0;
256
257 sigemptyset(&pending);
258 sigemptyset(&shpending);
259 sigemptyset(&blocked);
260 sigemptyset(&ignored);
261 sigemptyset(&caught);
262
263 if (lock_task_sighand(p, &flags)) {
264 pending = p->pending.signal;
265 shpending = p->signal->shared_pending.signal;
266 blocked = p->blocked;
267 collect_sigign_sigcatch(p, &ignored, &caught);
268 num_threads = get_nr_threads(p);
269 rcu_read_lock(); /* FIXME: is this correct? */
270 qsize = atomic_read(&__task_cred(p)->user->sigpending);
271 rcu_read_unlock();
272 qlim = task_rlimit(p, RLIMIT_SIGPENDING);
273 unlock_task_sighand(p, &flags);
274 }
275
276 seq_printf(m, "Threads:\t%d\n", num_threads);
277 seq_printf(m, "SigQ:\t%lu/%lu\n", qsize, qlim);
278
279 /* render them all */
280 render_sigset_t(m, "SigPnd:\t", &pending);
281 render_sigset_t(m, "ShdPnd:\t", &shpending);
282 render_sigset_t(m, "SigBlk:\t", &blocked);
283 render_sigset_t(m, "SigIgn:\t", &ignored);
284 render_sigset_t(m, "SigCgt:\t", &caught);
285 }
286
287 static void render_cap_t(struct seq_file *m, const char *header,
288 kernel_cap_t *a)
289 {
290 unsigned __capi;
291
292 seq_puts(m, header);
293 CAP_FOR_EACH_U32(__capi) {
294 seq_printf(m, "%08x",
295 a->cap[CAP_LAST_U32 - __capi]);
296 }
297 seq_putc(m, '\n');
298 }
299
300 static inline void task_cap(struct seq_file *m, struct task_struct *p)
301 {
302 const struct cred *cred;
303 kernel_cap_t cap_inheritable, cap_permitted, cap_effective, cap_bset;
304
305 rcu_read_lock();
306 cred = __task_cred(p);
307 cap_inheritable = cred->cap_inheritable;
308 cap_permitted = cred->cap_permitted;
309 cap_effective = cred->cap_effective;
310 cap_bset = cred->cap_bset;
311 rcu_read_unlock();
312
313 render_cap_t(m, "CapInh:\t", &cap_inheritable);
314 render_cap_t(m, "CapPrm:\t", &cap_permitted);
315 render_cap_t(m, "CapEff:\t", &cap_effective);
316 render_cap_t(m, "CapBnd:\t", &cap_bset);
317 }
318
319 static inline void task_seccomp(struct seq_file *m, struct task_struct *p)
320 {
321 #ifdef CONFIG_SECCOMP
322 seq_printf(m, "Seccomp:\t%d\n", p->seccomp.mode);
323 #endif
324 }
325
326 static inline void task_context_switch_counts(struct seq_file *m,
327 struct task_struct *p)
328 {
329 seq_printf(m, "voluntary_ctxt_switches:\t%lu\n"
330 "nonvoluntary_ctxt_switches:\t%lu\n",
331 p->nvcsw,
332 p->nivcsw);
333 }
334
335 static void task_cpus_allowed(struct seq_file *m, struct task_struct *task)
336 {
337 seq_printf(m, "Cpus_allowed:\t%*pb\n",
338 cpumask_pr_args(&task->cpus_allowed));
339 seq_printf(m, "Cpus_allowed_list:\t%*pbl\n",
340 cpumask_pr_args(&task->cpus_allowed));
341 }
342
343 int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
344 struct pid *pid, struct task_struct *task)
345 {
346 struct mm_struct *mm = get_task_mm(task);
347
348 task_name(m, task);
349 task_state(m, ns, pid, task);
350
351 if (mm) {
352 task_mem(m, mm);
353 mmput(mm);
354 }
355 task_sig(m, task);
356 task_cap(m, task);
357 task_seccomp(m, task);
358 task_cpus_allowed(m, task);
359 cpuset_task_status_allowed(m, task);
360 task_context_switch_counts(m, task);
361 return 0;
362 }
363
364 static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
365 struct pid *pid, struct task_struct *task, int whole)
366 {
367 unsigned long vsize, eip, esp, wchan = 0;
368 int priority, nice;
369 int tty_pgrp = -1, tty_nr = 0;
370 sigset_t sigign, sigcatch;
371 char state;
372 pid_t ppid = 0, pgid = -1, sid = -1;
373 int num_threads = 0;
374 int permitted;
375 struct mm_struct *mm;
376 unsigned long long start_time;
377 unsigned long cmin_flt = 0, cmaj_flt = 0;
378 unsigned long min_flt = 0, maj_flt = 0;
379 cputime_t cutime, cstime, utime, stime;
380 cputime_t cgtime, gtime;
381 unsigned long rsslim = 0;
382 char tcomm[sizeof(task->comm)];
383 unsigned long flags;
384
385 state = *get_task_state(task);
386 vsize = eip = esp = 0;
387 permitted = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS | PTRACE_MODE_NOAUDIT);
388 mm = get_task_mm(task);
389 if (mm) {
390 vsize = task_vsize(mm);
391 if (permitted) {
392 eip = KSTK_EIP(task);
393 esp = KSTK_ESP(task);
394 }
395 }
396
397 get_task_comm(tcomm, task);
398
399 sigemptyset(&sigign);
400 sigemptyset(&sigcatch);
401 cutime = cstime = utime = stime = 0;
402 cgtime = gtime = 0;
403
404 if (lock_task_sighand(task, &flags)) {
405 struct signal_struct *sig = task->signal;
406
407 if (sig->tty) {
408 struct pid *pgrp = tty_get_pgrp(sig->tty);
409 tty_pgrp = pid_nr_ns(pgrp, ns);
410 put_pid(pgrp);
411 tty_nr = new_encode_dev(tty_devnum(sig->tty));
412 }
413
414 num_threads = get_nr_threads(task);
415 collect_sigign_sigcatch(task, &sigign, &sigcatch);
416
417 cmin_flt = sig->cmin_flt;
418 cmaj_flt = sig->cmaj_flt;
419 cutime = sig->cutime;
420 cstime = sig->cstime;
421 cgtime = sig->cgtime;
422 rsslim = ACCESS_ONCE(sig->rlim[RLIMIT_RSS].rlim_cur);
423
424 /* add up live thread stats at the group level */
425 if (whole) {
426 struct task_struct *t = task;
427 do {
428 min_flt += t->min_flt;
429 maj_flt += t->maj_flt;
430 gtime += task_gtime(t);
431 } while_each_thread(task, t);
432
433 min_flt += sig->min_flt;
434 maj_flt += sig->maj_flt;
435 thread_group_cputime_adjusted(task, &utime, &stime);
436 gtime += sig->gtime;
437 }
438
439 sid = task_session_nr_ns(task, ns);
440 ppid = task_tgid_nr_ns(task->real_parent, ns);
441 pgid = task_pgrp_nr_ns(task, ns);
442
443 unlock_task_sighand(task, &flags);
444 }
445
446 if (permitted && (!whole || num_threads < 2))
447 wchan = get_wchan(task);
448 if (!whole) {
449 min_flt = task->min_flt;
450 maj_flt = task->maj_flt;
451 task_cputime_adjusted(task, &utime, &stime);
452 gtime = task_gtime(task);
453 }
454
455 /* scale priority and nice values from timeslices to -20..20 */
456 /* to make it look like a "normal" Unix priority/nice value */
457 priority = task_prio(task);
458 nice = task_nice(task);
459
460 /* convert nsec -> ticks */
461 start_time = nsec_to_clock_t(task->real_start_time);
462
463 seq_printf(m, "%d (%s) %c", pid_nr_ns(pid, ns), tcomm, state);
464 seq_put_decimal_ll(m, ' ', ppid);
465 seq_put_decimal_ll(m, ' ', pgid);
466 seq_put_decimal_ll(m, ' ', sid);
467 seq_put_decimal_ll(m, ' ', tty_nr);
468 seq_put_decimal_ll(m, ' ', tty_pgrp);
469 seq_put_decimal_ull(m, ' ', task->flags);
470 seq_put_decimal_ull(m, ' ', min_flt);
471 seq_put_decimal_ull(m, ' ', cmin_flt);
472 seq_put_decimal_ull(m, ' ', maj_flt);
473 seq_put_decimal_ull(m, ' ', cmaj_flt);
474 seq_put_decimal_ull(m, ' ', cputime_to_clock_t(utime));
475 seq_put_decimal_ull(m, ' ', cputime_to_clock_t(stime));
476 seq_put_decimal_ll(m, ' ', cputime_to_clock_t(cutime));
477 seq_put_decimal_ll(m, ' ', cputime_to_clock_t(cstime));
478 seq_put_decimal_ll(m, ' ', priority);
479 seq_put_decimal_ll(m, ' ', nice);
480 seq_put_decimal_ll(m, ' ', num_threads);
481 seq_put_decimal_ull(m, ' ', 0);
482 seq_put_decimal_ull(m, ' ', start_time);
483 seq_put_decimal_ull(m, ' ', vsize);
484 seq_put_decimal_ull(m, ' ', mm ? get_mm_rss(mm) : 0);
485 seq_put_decimal_ull(m, ' ', rsslim);
486 seq_put_decimal_ull(m, ' ', mm ? (permitted ? mm->start_code : 1) : 0);
487 seq_put_decimal_ull(m, ' ', mm ? (permitted ? mm->end_code : 1) : 0);
488 seq_put_decimal_ull(m, ' ', (permitted && mm) ? mm->start_stack : 0);
489 seq_put_decimal_ull(m, ' ', esp);
490 seq_put_decimal_ull(m, ' ', eip);
491 /* The signal information here is obsolete.
492 * It must be decimal for Linux 2.0 compatibility.
493 * Use /proc/#/status for real-time signals.
494 */
495 seq_put_decimal_ull(m, ' ', task->pending.signal.sig[0] & 0x7fffffffUL);
496 seq_put_decimal_ull(m, ' ', task->blocked.sig[0] & 0x7fffffffUL);
497 seq_put_decimal_ull(m, ' ', sigign.sig[0] & 0x7fffffffUL);
498 seq_put_decimal_ull(m, ' ', sigcatch.sig[0] & 0x7fffffffUL);
499
500 /*
501 * We used to output the absolute kernel address, but that's an
502 * information leak - so instead we show a 0/1 flag here, to signal
503 * to user-space whether there's a wchan field in /proc/PID/wchan.
504 *
505 * This works with older implementations of procps as well.
506 */
507 if (wchan)
508 seq_puts(m, " 1");
509 else
510 seq_puts(m, " 0");
511
512 seq_put_decimal_ull(m, ' ', 0);
513 seq_put_decimal_ull(m, ' ', 0);
514 seq_put_decimal_ll(m, ' ', task->exit_signal);
515 seq_put_decimal_ll(m, ' ', task_cpu(task));
516 seq_put_decimal_ull(m, ' ', task->rt_priority);
517 seq_put_decimal_ull(m, ' ', task->policy);
518 seq_put_decimal_ull(m, ' ', delayacct_blkio_ticks(task));
519 seq_put_decimal_ull(m, ' ', cputime_to_clock_t(gtime));
520 seq_put_decimal_ll(m, ' ', cputime_to_clock_t(cgtime));
521
522 if (mm && permitted) {
523 seq_put_decimal_ull(m, ' ', mm->start_data);
524 seq_put_decimal_ull(m, ' ', mm->end_data);
525 seq_put_decimal_ull(m, ' ', mm->start_brk);
526 seq_put_decimal_ull(m, ' ', mm->arg_start);
527 seq_put_decimal_ull(m, ' ', mm->arg_end);
528 seq_put_decimal_ull(m, ' ', mm->env_start);
529 seq_put_decimal_ull(m, ' ', mm->env_end);
530 } else
531 seq_printf(m, " 0 0 0 0 0 0 0");
532
533 if (permitted)
534 seq_put_decimal_ll(m, ' ', task->exit_code);
535 else
536 seq_put_decimal_ll(m, ' ', 0);
537
538 seq_putc(m, '\n');
539 if (mm)
540 mmput(mm);
541 return 0;
542 }
543
544 int proc_tid_stat(struct seq_file *m, struct pid_namespace *ns,
545 struct pid *pid, struct task_struct *task)
546 {
547 return do_task_stat(m, ns, pid, task, 0);
548 }
549
550 int proc_tgid_stat(struct seq_file *m, struct pid_namespace *ns,
551 struct pid *pid, struct task_struct *task)
552 {
553 return do_task_stat(m, ns, pid, task, 1);
554 }
555
556 int proc_pid_statm(struct seq_file *m, struct pid_namespace *ns,
557 struct pid *pid, struct task_struct *task)
558 {
559 unsigned long size = 0, resident = 0, shared = 0, text = 0, data = 0;
560 struct mm_struct *mm = get_task_mm(task);
561
562 if (mm) {
563 size = task_statm(mm, &shared, &text, &data, &resident);
564 mmput(mm);
565 }
566 /*
567 * For quick read, open code by putting numbers directly
568 * expected format is
569 * seq_printf(m, "%lu %lu %lu %lu 0 %lu 0\n",
570 * size, resident, shared, text, data);
571 */
572 seq_put_decimal_ull(m, 0, size);
573 seq_put_decimal_ull(m, ' ', resident);
574 seq_put_decimal_ull(m, ' ', shared);
575 seq_put_decimal_ull(m, ' ', text);
576 seq_put_decimal_ull(m, ' ', 0);
577 seq_put_decimal_ull(m, ' ', data);
578 seq_put_decimal_ull(m, ' ', 0);
579 seq_putc(m, '\n');
580
581 return 0;
582 }
583
584 #ifdef CONFIG_CHECKPOINT_RESTORE
585 static struct pid *
586 get_children_pid(struct inode *inode, struct pid *pid_prev, loff_t pos)
587 {
588 struct task_struct *start, *task;
589 struct pid *pid = NULL;
590
591 read_lock(&tasklist_lock);
592
593 start = pid_task(proc_pid(inode), PIDTYPE_PID);
594 if (!start)
595 goto out;
596
597 /*
598 * Lets try to continue searching first, this gives
599 * us significant speedup on children-rich processes.
600 */
601 if (pid_prev) {
602 task = pid_task(pid_prev, PIDTYPE_PID);
603 if (task && task->real_parent == start &&
604 !(list_empty(&task->sibling))) {
605 if (list_is_last(&task->sibling, &start->children))
606 goto out;
607 task = list_first_entry(&task->sibling,
608 struct task_struct, sibling);
609 pid = get_pid(task_pid(task));
610 goto out;
611 }
612 }
613
614 /*
615 * Slow search case.
616 *
617 * We might miss some children here if children
618 * are exited while we were not holding the lock,
619 * but it was never promised to be accurate that
620 * much.
621 *
622 * "Just suppose that the parent sleeps, but N children
623 * exit after we printed their tids. Now the slow paths
624 * skips N extra children, we miss N tasks." (c)
625 *
626 * So one need to stop or freeze the leader and all
627 * its children to get a precise result.
628 */
629 list_for_each_entry(task, &start->children, sibling) {
630 if (pos-- == 0) {
631 pid = get_pid(task_pid(task));
632 break;
633 }
634 }
635
636 out:
637 read_unlock(&tasklist_lock);
638 return pid;
639 }
640
641 static int children_seq_show(struct seq_file *seq, void *v)
642 {
643 struct inode *inode = seq->private;
644 pid_t pid;
645
646 pid = pid_nr_ns(v, inode->i_sb->s_fs_info);
647 seq_printf(seq, "%d ", pid);
648
649 return 0;
650 }
651
652 static void *children_seq_start(struct seq_file *seq, loff_t *pos)
653 {
654 return get_children_pid(seq->private, NULL, *pos);
655 }
656
657 static void *children_seq_next(struct seq_file *seq, void *v, loff_t *pos)
658 {
659 struct pid *pid;
660
661 pid = get_children_pid(seq->private, v, *pos + 1);
662 put_pid(v);
663
664 ++*pos;
665 return pid;
666 }
667
668 static void children_seq_stop(struct seq_file *seq, void *v)
669 {
670 put_pid(v);
671 }
672
673 static const struct seq_operations children_seq_ops = {
674 .start = children_seq_start,
675 .next = children_seq_next,
676 .stop = children_seq_stop,
677 .show = children_seq_show,
678 };
679
680 static int children_seq_open(struct inode *inode, struct file *file)
681 {
682 struct seq_file *m;
683 int ret;
684
685 ret = seq_open(file, &children_seq_ops);
686 if (ret)
687 return ret;
688
689 m = file->private_data;
690 m->private = inode;
691
692 return ret;
693 }
694
695 int children_seq_release(struct inode *inode, struct file *file)
696 {
697 seq_release(inode, file);
698 return 0;
699 }
700
701 const struct file_operations proc_tid_children_operations = {
702 .open = children_seq_open,
703 .read = seq_read,
704 .llseek = seq_lseek,
705 .release = children_seq_release,
706 };
707 #endif /* CONFIG_CHECKPOINT_RESTORE */
Linux with added FPC-III support